Japanese Unexamined Patent Application Publication No. 2000-260283 (Patent Literature 1) discloses one example of an electromagnetic-relay seal structure. In this seal structure, an opening side of a case is filled with a sealing material and cured, to ensure sealing properties inside the case. For preventing inflow of the sealing material through the opening where a movable terminal is protruded, a projection is provided inside a case, and/or a cut-and-raised part is provided in a movable contact terminal.